instantOS has a notification center similar to android. Notifications will appear in a bubble at the top left of the screen, stay there for a while and then automatically disappear. They can also be closed by right clicking on them.
Application defined context actions like confirmation prompts or just shortcuts to where the notification comes from are available by left clicking on the bubble.
All past notifications are accessible and can be managed in the notification center. The notification center is started with Super+G and can be closed with escape or right clicking on it.
Notifications can be read from the notification center by left clicking on them. This opens up the notification menu where the content can be read or managed.
Notifications can either be deleted individually by selecting them and choosing the delete option or by pressing Shift+left/right in the notification center where you can delete notifications that contain a certain keyword, come from a specific application or you van just clear all of them.
Notifications are persistent between reboots unless specifically removed. This means that over a long period of usage the list can get quite long. In order to keep good performance the notification center only displays up to 700 notifications at a time. If the total number of notifications exceeds 700 then notifications will be divided into pages with 700 notifications each. At the bottom of each page (which can be reachoed by scrolling down) is a next button to load and view the next page.